What does it need?

How to compile it?

Cerius uses nasm as the assembler and GCC as the compiler.
You'll also need make.
To create the image, which can be emulated or written to a real disk, do a make harddisk.img

How to run it?

After you create the image, you can use an emulator (like Bochs, Qemu or Virtualbox).
If you have Qemu installed, you can do a quick make simqemu.
You may also write the image on a real disk and boot real hardware from it (dd or Rufus should be fine).
To run it on real hardware, you'll also need an AMD64 CPU.